Locally Recurrent Rectal Cancer According to a Standardized MRI Classification System: A Systematic Review of the Literature

Abstract

(1) Background: The classification of locally recurrent rectal cancer (LRRC) is not currently standardized. The aim of this review was to evaluate pelvic LRRC according to the Beyond TME (BTME) classification system and to consider commonly associated primary tumour characteristics. (2) Methods: A systematic review of the literature prior to April 2020 was performed through electronic searches of the Science Citation Index Expanded, EMBASE, MEDLINE, and CENTRAL databases. The primary outcome was to assess the location and frequency of previously classified pelvic LRRC and translate this information into the BTME system. Secondary outcomes were assessing primary tumour characteristics. (3) Results: A total of 58 eligible studies classified 4558 sites of LRRC, most commonly found in the central compartment (18%), following anterior resection (44%), in patients with an ‘advanced’ primary tumour (63%) and following neoadjuvant radiotherapy (29%). Most patients also classified had a low rectal primary tumour. The lymph node status of the primary tumour leading to LRRC was comparable, with 52% node positive versus 48% node negative tumours. (4) Conclusions: This review evaluates the largest number of LRRCs to date using a single classification system. It has also highlighted the need for standardized reporting in order to optimise perioperative treatment planning.

Local Recurrences in Rectal Cancer: MRI vs. CT

“…A recent review including a total of 58 studies and 3975 patients with locally recurrent rectal cancer classified according to BTME system reports that most recurrences occur in the central compartment (including the rectum and perirectal fat), followed by the lateral compartment (involving the external iliac vessels and lymph nodes, the piriformis muscle, and the internal obturator). Many cases of recurrence are reported in the posterior (involving the pre-sacral fascia, sacrum, and sciatic nerve) and anterior below peritoneal reflection (including the genitourinary structures and pubic symphysis) compartments, with much lower numbers or no LRs within the anterior above, anterior urogenital (including the urethra, the introitus vaginal, and the crus penis), and infra-elevator compartments (involving the elevator of the anus muscle and the external sphincter) [ 23 ].…”

Post-Surgical Imaging Assessment in Rectal Cancer: Normal Findings and Complications

“…The most important prognostic factor in case of LR is the possibility of obtaining a free resection margin (R0) after surgical treatment. This circumstance only occurs in 60% of cases [ 82 ], and the site of recurrence is significant in this regard. According to reports from the Mayo Clinic and the Memorial Sloan-Kettering Cancer Center (MSKCC) [ 83 , 84 ], the LR sites could be classified into four categories: (1) Axial (or central): includes anastomotic recurrence after low anterior resection, local recurrence after transanal or trans-sphincteric excision, and perineal recurrence after abdominoperineal resection.…”

From Dukes-MAC Staging System to Molecular Classification: Evolving Concepts in Colorectal Cancer

“…Anterior urogenital (Perineal, vaginal, distal urethra, crus penis). The worse survival was reported for patients with tumors located in the first compartment (anterior below peritoneal reflection) same as for those with tumors involving multiple compartments [ 35 ].…”